Australian mean annual temperature reconstruction 1882-2009

After getting questions from people about the BoM claim that 2000-2009 was Australia’s hottest decade I have started updating my 1992 25 station series for Australian – time consuming with 50 other things to do.

Here is the result of an experiment to fit my 1993 25 station series to the Spencer and Christy lower troposphere satellite data for a block of lats-longs forming the Australian region.

(Sorry Tasmania is missed out. Not worth including all that ocean just to get the Apple Isle.)

The BoM does not use pre-1910 data, I expect they would claim that Stevenson Screens were not in use before that date and the old open thermometer stands read warm. I think they are wrong about that – see my published paper.

My 25 station series would incorporate a small quota of urban warming from the town sites. Like all temperature time series, mine would get less reliable the older the data is – but I put this up as the best Australian series of its length.

Perhaps somebody knows of proxy records that cast light on late 19C warmth in Australia.

Here in Spokane (Eastern Washington State, US) we’re having an unusually mild winter. Last year we broke the all time snow record. Go figure. So right now we’re probably one of the places the warmers will point to in order to support their position. 🙂

Your graph looks pretty consistent with a lot of other reconstructions that I’ve seen people doing. Once the estimated UHI is factored out is there ANY land based warming signal from 1970 onwards?

How much does a Stevenson Screen modify temp readings?
What issues ore involved in making sure the SS is properly put together?

Several interesting points here.
First, the correspondence between the satellite and the ground data is impressive. In fact it is amazing for the ten years 1983-92 – probably the closest match of satellite and ground data in any legitimate, untweaked comparison of real raw data.

Second, that begs the question whether the correspondence continues after 1992. If so, then you have nailed it as far as a composite Australian temperature series is concerned, and also reinforced the reliability of the satellite data which are compiled by a completely independent method. It would be very interesting to see how your composite performs after 1992, and also to compare it to the BoM’s composite here.

Third, the scaling is interesting. Christy has told McIntyre, and McIntyre has verified in several comparisons, that the best matches of global or tropical surface to satellite data are found with a ratio of 1.2 satellite:surface. In other words, the temperatures line up best if you divide the satellite anomalies by 1.2 before comparing with the surface anomalies. The idea is that temperatures in the mid-troposphere vary a bit more than they do at the surface. Your graph appears to get an excellent correspondence with a ratio of 0.75 – i.e. with the satellite anomalies being divided by 0.75 before comparison with the surface data. It seems quite plausible that surface land temperatures would vary a lot more than surface sea temperatures, but your series may help nail down the exact ratios. Bravo!

This is interesting Tim, you say “This is evidence of site error” – well those BoM data are from many sites and well stroked & tweaked – their max, min etc series are downloadable, so you could run your digital ruler over them.

I am familiar with the notion of DTR and have done some work on it in 90’s – and have always thought that a good part of the claimed closing of global DTR was due to increasing min in the UHI. I was not aware that Australian DTR was expanding for a few years – will keep an eye out when looking at station numbers. This paper I have critiqued below by Easterling et al 1997 is the last notable paper I am aware of on global DTR.

Senior staff from USA climate giant NOAA / NCDC are responsible for the definitive recent paper on global Daily Temperature Range (DTR).Easterling, D.R. et al., 1997, Maximum and minimum temperature trends for the globe, Science, 277, 364-367.
Read about systemic faults in their data, plus the usual “turn a blind eye to the UHI” methodology and see for yourself the most error ridden colour diagram ever to appear in a modern climate Journal.
Your taxes at work.

Re Stevenson screens and my claim that use was widespread prior to 1910 vs the BoM who say they were little used until the BoM was formed in 1908. A kind reader has sent in this list from old newspaper records from our colonial days searcheable at this National Library website.
Amazing stuff, how interested they must have been in science to record these things – the likes of which would be ignored today.
17 Jan 1887 Brisbane Courier – a full story on the Brisbane Observatory complete with Stevenson screen

30 May 1898 Brisbane Courier – Full report of Kosciusko Observatory, started December 1897 with description of all equipment including Stevenson screen (I looked for this station at BoM -couldn’t find it ?? Would have been interesting at this elevation)

According to Bill Gibbs “A mini-history of meteorology in Australia” in “Windows on Meteorology” edited by Eric K Webb (CSIRO publishing-ISBN 0643060383). Photo on page 92 (Figure 13.8) shows a Stevenson screen next to snowed in hut. Caption reads “The observatory site established in December 1897 by Clement Wragge on the summit of Australia’s highest peak, Mt Kosciusko (2228m). From the outset observers lived and worked in tents at the site and recorded observations every four hours throughout the twenty-four, right through the year. A permanent hut was built in April 1898 to replace the tents. the hut in mid-winter conditions is seen here in a photograph taken in July 1899. The observations were terminated in mid- 1902 because the NSW government withdraw financial support (photo Snowy Mountains Hydro Electric Authority)”